CA2266916C - Inflatable watercraft - Google Patents

Abstract

A powered inflatable watercraft comprises a generally U--shaped floatation member having two laterally spaced apart side portions each having a forward end and a rearward end, and a front end portion extending between the forward ends.
The watercraft further comprises a seat member disposed between the side portions and the front end portion, and having a front seat surface adjacent the front end portion and a generally unobstructed, transversely extending rear seat surface disposed oppositely from said front seat surface. The watercraft further comprises a drive unit for propelling the watercraft and being secured beneath the seat member to be clear of an operator's legs.

Description

INFLATABLE WATERCRAFT
BACKGROiJND OF THE INVENTION

This invention relates to a powered inflatable watercraft, particularly for fishing.

Inflatable watercraft are popular among fishermen and water enthusiasts as such watercraft are readily transportable, light weight and relatively inexpensive.
Generally, such an inflatable watercraft comprises a sleeve-like skin enclosing an air bladder which is inflatable and deflatable. While these types of inflatable watercraft are commonly circular in shape, they can also be U-shaped or have interconnected straight parallel pontoon configurations. Typically an operator manually powers such a watercraft by kicking his legs, which is both slow and tiring to the operator. To overcome this problem, inflatable watercraft with powered drive units have been developed.

United States Patent No. 4,938,722 issued to Rizley discloses a fisherman's float propelling system. The system includes a toric fishing float, a non-buoyant fabric sling seat attached to the fishing float for supporting an operator, a propulsion means attached to a leg of the operator, and a battery for powering the propulsion means supported by an auxiliary float. When the system is in water, the operator sits on the fabric sling seat which sags below the fishing float, thereby increasing the drag on the watercraft. While seated, the operator's lower body is submersed in the water and in order for the operator to stay dry, he would have to wear watertight clothing.
Further, if the water temperature was cold, the operator would have to wear insulated clothing to remain at a comfortable temperature.

-2-The propulsion means disclosed by Rizley is a trolling motor having a propeller which is surrounded by a guard, and forces generated by the propeller are resisted by the operator's leg, which can be tiring. Also, if the guard becomes detached from the propulsion means, the operator is likely to be injured because the propeller would be exposed directly to the operator's legs. When transporting the system, the operator would need to deflate two separate floats and take great care in disconnecting the floats and the propulsion means.

United States Patent No. 4,911,094 issued to Akers discloses a powered floater. The floater includes a buoyant member, a non-buoyant webbed seat attached to the buoyant member for supporting an operator, and a separate float tube having a battery and an electric motor for turning a propeller. The operator of the floater would have his lower body submersed in the water, which leads to the same problems as discussed in the Rizley patent above.
Further, as the buoyant member and float tube are separate, the operator would need to spend time and effort deflating and disconnecting the member and tube for transportation purposes.

United States Patent No. 4,021,873 issued to Francois discloses a circular watercraft. Francois addresses the problems encountered by Akers and Rizley due to the operator's lower body being submersed in water. In Francois the watercraft includes a buoyant hull supporting a rigid deck having an opening to receive a power means to drive and steer the watercraft. The deck could include a seat to support the operator or the operator could stand or sit directly on the rigid deck. However Francois also discloses a stabilizer assembly to lend horizontal and vertical stability to the watercraft, which makes the watercraft difficult to disassemble and transport.

-3-The problems encountered by Akers and Rizley due to the operator's lower body being submersed in water is also addressed by United States Patent No. 5,643,031 issued to Fenton et al. Fenton discloses an aquatic vehicle which includes an egg-like configured support frame, a cover attached to the perimeter of the frame and enclosing a buoyant float, and a non-buoyant seat attached to the support frame. In the water, an operator is supported by the seat. Depending on the weight of the operator, the support frame can be adjusted relative to the cover so that the seat can be positioned above the water. However, the position of the support frame relative to the cover can not be adjusted once the operator is sitting on the seat and this may cause difficulties in making the correct adjustment for the person's weight. Further, Fenton does not disclose a drive unit for powering the vehicle.
United States Patent No. 5,601,461 issued to Mills discloses a float tube propulsion apparatus which can be releasably connected to a float tube. An operator must spend time and effort connecting the apparatus and the float tube before using the apparatus. Further the operator must spend time and effort disconnecting the apparatus and the float tube so that the operator can efficiently transport and store the apparatus and the float tube.

A common problem with inflatable watercraft relates to controlling inflation pressure within air chambers of the watercraft due to temperature variations or possible slow leakage of air due to porosity or small openings in the walls of the air chamber. In hot weather, bodies of water are normally much colder than air temperature and thus a watercraft that has been inflated on the shore to a suitable pressure is chilled by cold water and the pressure in the chambers is reduced, losing rigidity and floatation.
In these circumstances, with extreme pressure loss, the

-4-person is forced to return to shore to apply additional pressure. Also, it is not unusual for a watercraft to be accidentally punctured during use, and this also can cause deflation of the vessel, forcing the operator to return to shore.

What would be desirable therefore is a powered inflatable watercraft which does not require an operator's lower body to be submersed in water during operation, does not require assembly before use, does not require disassembly before transportation and storage, and is not hazardous to the operator's legs. Also, it would be advantageous to reduce drag by providing a seat with adequate floatation and support to prevent the operator's lower torso from projecting into the water. In addition, it would be an advantage to be able to control inflation pressure of air chambers of the watercraft when the watercraft is remote from the shore and normal on-shore inflation apparatus is not available to overcome pressure loss due to cooling of air within the air chambers, which disturbs rigidity and trim of the watercraft.

BRIEF SUNIIKARY OF THE INVENTION

The present invention addresses the above problems by providing a simple, light weight powered inflatable watercraft which does not require an operator's lower torso to be submersed in water during operation, does not require assembly before use, does not require disassembly before transportation and storage, and is not hazardous to the operator's legs. The invention has a separately inflatable seat, which in combination with other structure, supports the operator's lower torso to prevent excessive projection into the water with a corresponding decrease in drag. In addition, the present invention provides a means for controlling inflation pressure of separate chambers of the watercraft, thus enabling pressure to be increased within -particular chambers as required to compensate for cooling, and also to permit accurate trim of the watercraft.

5 In accordance with one aspect of the invention, there is provided a watercraft comprising: a generally U-shaped floatation member having two laterally spaced apart side portions each having a forward end, a rearward end and a top surface; and a front end portion extending between said forward ends; a seat member disposed between said side portions and said front end portion, said seat member having a front seat surface adjacent the front end portion and a generally unobstructed, transversely extending rear seat surface disposed oppositely from said front seat surface; a rigid hull member located beneath said seat member and having a lower surface bulging downwardly below said floatation member; and a drive unit for propelling said watercraft secured beneath said rigid hull member adjacent to a central longitudinal axis of said rigid hull member and generally adjacent a vertical axis passing through a centre of gravity of the loaded watercraft.

Preferably, the seat member has a bottom seat surface and two side seat surfaces, each being complementary to and adjacent one of the side portions. The front seat surface is complementary with the front end portion and the rear seat surface is disposed forwardly of the rearward ends of the floatation member.

- 5a -Preferably, the rigid hull member has a forward edge connected to the front end portion, and two side edges each connected to one of the side portions.

Preferably, the drive unit includes an electric motor and a propeller rotatable about a generally horizontal axis. The drive unit further

-6-includes a battery holder located on the floatation member, a manual control unit located within reach of an operator, and electrical conduits extending from the battery holder to the control unit and from the control unit to the drive unit to permit control of electrical power supplied to the drive unit.

Preferably, the watercraft has a back support member extending upwardly above the front end portion.
Preferably, the watercraft has an air compressor unit having a discharge, and air conduits extending from the discharge to each of the floatation member, seat member and back support member. Each of the air conduits have a respective control valve allowing the floatation member, seat member and back support member to be independently inflated and deflated. The watercraft also has electrical conduits extending from the compressor to the control unit to permit control of the compressor.
Preferably, the watercraft has two forwardly facing mirrors located adjacent respective side portions of the floatation member.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

In drawings which illustrate embodiments of the invention, Figure 1 is a perspective view according to a first embodiment of the invention;

Figure 2 is a top plan view according to the first embodiment of the invention;

Figure 3 is a rear view according to the first embodiment of the invention;

-7-Figure 4 is a bottom view according to the first embodiment of the invention;

Figure 5 is a side view according to the first embodiment of the invention, shown with an operator, in broken outline, sitting in the invention; and Figure 6 is a longitudinal cross-section view taken along line 6-6 of Figure 2.
DETAILED DESCRIPTION OF THE INVENTION

Referring to mainly to Figure 1, an apparatus according to a first embodiment of the invention is shown generally at 10.

The apparatus 10 includes a generally U-shaped floatation member 12 having two laterally spaced apart side portions 14 and 16 having respective forward ends 18 and 20, rearward ends 22 and 24, and top surfaces 26 and 28. The floatation member 12 also has a front end portion 30 extending between said forward ends 18 and 20. The portions 14, 16 and 30 are generally coplanar, and have generally circular cross-sections shown in Figures 3 and 6, and typically are about 15 inches in diameter.

The apparatus 10 further includes a seat member 32 disposed between said side portions 14 and 16 and said front end portion 30. The seat member 32 has a curved front seat surface 34, shown in Figure 6, which is complementary to and located adjacent the front end portion 30. The seat member 32 has two side seat surfaces 36 and 38, shown in Figure 3, which are complementary to and adjacent respective side portions 14 and 16. The seat member 32 also has a transversely extending rear seat surface 40 disposed oppositely from said front seat surface and forwardly of said rearward ends 22 and 24. Further, the

-8-seat member 32 has a seating surface 42 upon which an operator sits and a bottom seat surface 44. The operator faces rearwardly (see Figure 5), and the rear seat surface 40 is generally unobstructed to permit relatively easy access for the operator. This contrasts with many prior art watercraft where the operator's feet, sometimes wearing swim fins, must pass through a narrow gap between a rear edge of the seat and a rear portion of the watercraft. The apparatus further includes a back support member 46 which is complementary to and extends upwardly above the front end portion 30.

The floatation member 12, the seat member 32 and the back support member 46, have a respective floatation cover 100, seat cover 102, and back support cover 104. The floatation cover 100 has a bottom half 106 made of a heavy canvas which can withstand abrasion caused by the watercraft running up on a beach or the force of the watercraft hitting a submerged obstacle in the water, and a top half 108 made of a heavy duty nylon. The seat cover 102 and the back support cover 104 are also made of a heavy duty nylon.
Each of the covers 100, 102 and 104 enclose a respective floatation bladder, seat bladder, and back support bladder which are made of a flexible airtight material to provide respective air chambers which are separately inflatable and deflatable, as will be described.

The apparatus further includes a rigid hull member 47, shown in Figure 4, which is made of a light weight yet relatively stiff material, such as sheet metal, eg.
aluminum, or a plastic. The rigid hull member 47 has a curved forward edge 48 connected to said front end portion 30 and two straight side edges 50 and 52, each side edge being connected to one of said side portions 14 and 16 respectively. The three edges 48, 50 and 52 of the hull member 47 are securely connected in a releasable manner to the floatation member 12 to permit easy removal of the hull

-9-member 47 for servicing. As seen in Figure 3, the rigid hull member 47 also has two obliquely inclined planar side surfaces 54 and 56, each sloping downwardly from the side edges 50 and 52 respectively to merge into a generally triangular planar centre surface 58. The centre surface 58 slopes downwardly and rearwardly about 2 - 3 degrees when viewed transversely in Figure 6, and thus it can be seen that the member 47 has a lower surface bulging downwardly below the floatation member. The bottom seat surface 44 is generally complementary to the shape of the hull member 47 to be supported thereon.

The apparatus 10 further includes a drive unit 60, shown in Figure 6, extending downwardly from the hull member 47.
The drive unit 60 is connected adjacent to a central longitudinal axis of the rigid hull 47. The drive unit has a tubular strut 61 with a screw-threaded upper end 63 which extends through an opening in the centre surface 58 and is secured thereto by lower and upper nuts 65 and 69. When the nuts 65 and 69 are tightened on the strut 61 to secure the strut 61 rigidly to the rigid hull member 47, the strut 61 is disposed generally perpendicularly to the centre surface 58 of the rigid hull member 47. The strut 61 also has a lower end 67 connected to a motor housing 64 containing an electric motor which drives a conventional propeller 62 about an axis which is also approximately 2 to 3 degrees inclined to the horizontal when the apparatus is correctly trimmed due to the slope of the surface 58. The drive unit 60 also has a cap-type marine fitting 59 which is located at the upper end 63 of the strut 61 to permit "breathing" of the housing as will be explained.

The apparatus further includes a manual control unit 66 located in a rigid container adjacent the top surface 26 near the rearward end 22. The apparatus further includes a first set of electrical conduits 68 extending from the control unit 66 to a battery holder 70 located in an

-10-opening 72 at the top of the back support member 46. The battery holder 70 is generally adjacent a central longitudinal axis of the apparatus. There are also a second set of electrical and air conduits 74 extending from the control unit 66 to the marine fitting 59 and down the strut 61 to the electric motor in the motor housing 64.
The air conduit is routed with the electrical conduit for convenience, and communicates with the housing 64 to permit breathing thereof while preventing ingress of water. The control unit 66 has a motor speed control to vary speed of the motor. The battery holder 70 is a rigid moulded plastic box which is set into the back support bladder and adapted to hold a small, lightweight, high capacity, sealed, on-board battery (not shown), similar to the type of battery used to power an electric wheel chair.

The apparatus further includes two side storage compartments 76 and 78 extending upwardly above said top surfaces 26 and 28 and having releasable top covers, eg.
securable with zip fasteners. The apparatus also includes an on-board air compressor 80 with a discharge, and an air tube 81 with a first end releasably connected to the discharge and a second end connected to an air distribution manifold 82, the compressor and manifold being located in the storage compartment 76. Undesignated electrical conduits extend between the control unit 66 to the air compressor 80 for supplying power thereto. The compressor draws little current and generates a small pressure increase sufficient to inflate the bladders to one or two psi above atmospheric pressure. A suitable compressor that is commonly used to provide air pressure for bladders located in automobile seat backs to help correct an user's posture can be selected for the present invention. There are three air conduits 84, 86 and 88 extending from the manifold 82 to the floatation bladder, seat bladder and back support bladder, respectively. Each of the air conduits 84, 86 and 88 have a respective control valve 85, -- ----------

-11-87 and 89 for independently inflating and deflating the floatation bladder, seat bladder, and back support bladder respectively. Each valve has an open position to permit inflation and deflation and a closed position to hold the pressure of the bladders. The valves 85, 87 and 89 are manually actuated by the operator and accessible through the releasable cover of the compartment 76.

In summary, it can be seen that the apparatus 10 has a control unit which can control the speed of the electric motor and the actuation of the air compressor 80. The three control valves permit control of pressure in each of the separate bladders, permitting accurate control of trim of the watercraft, thus reducing drag when the vessel is required to cover relatively large distances across a body of water. The operator can adjust inflation pressure of the three bladders while the operator is sitting on the seat and is remote from the shore, thus compensating for pressure loss due to cooling from the cold water. The use of the compressor and control valves also permits addition of air to one or more bladders which may have been accidentally punctured by contact with underwater obstructions thus enabling the operator to return to shore safely, assuming that output from the compressor can accommodate loss of air pressure due to the puncture.
Thus, independent remote control of the inflation of the three bladders of the vessel permit efficient inflation of the chambers, as well as providing a degree of safety not found in prior art apparatus.
The apparatus is also provided with two retractable forwardly facing mirrors 92 and 94, shown in retracted and extended positions respectively. Each mirror is connected by a respective axially aligned swivel to one of the side storage compartments 76 and 78. When both the mirrors are extended by rotating outwardly, the operator can see forwardly more easily than in prior art craft. Also, seat

-12-belt portions 96 are provided adjacent the seat surface to enable the operator to strap himself to the seat for safety in rough water conditions.

Operation To prepare the watercraft for use, the operator disconnects the air tube 81 from the discharge of the on-board air compressor 80 and connects the air tube 81 to a larger on-shore air compressor (not shown) which eliminates the need to use the smaller compressor 80, thus saving time and use of the on-board battery. The on-shore air compressor is used to inflate the floatation bladder to a pressure sufficient to provide buoyancy to the apparatus 10 and stiffness to the floatation member 12. The seat bladder is independently inflated to a pressure sufficient to provide additional buoyancy to the apparatus 10, to provide stiffness in the seat member 32 to support the operator so that the operator's lower torso is not submersed in the water, and to push the bottom seat surface 44 to a position adjacent the rigid hull member 47. The back support bladder is also independently inflated to a pressure sufficient to provide stiffness in the back support member 46 to support the operator's back and to prevent the collapse of the seat member 32. Once the bladders are filled using the on-shore air compressor, the air tube 81 is disconnected from the on-shore air compressor and re-connected to the on-board air compressor 80. The operator, shown in dotted outline in Figure 5, sits on the seat member 32 and can operate the manual control unit 66 and the control valves 85, 87 and 89 to independently control the pressure in bladders while the watercraft is in operation. After several hours of operation on the water, it may be necessary for the operator to adjust the pressure in the floatation bladder and the seat bladder to provide sufficient buoyancy so that the watercraft obtains optimum

-13-trim to reduce drag and keep the operator's torso out of the water, and also to reduce operator fatigue.

The operator can also operate the manual control unit 66 to control the speed of the electric motor. As the drive unit 60 is fixed, it cannot contribute materially to steering of the watercraft. Steering is accomplished by the swim fins provided on the operator's feet and, when the operator's legs are extended, the fins act as rudders to steer the craft when powered by the propeller, thus reducing operator fatigue. Clearly, if the battery looses power due to excessive use, low temperature or other situation, the operator can propel himself back to the shore and safety by using his swim fins as in the prior art. When the watercraft is to be transported or stored, each of said bladders is fully deflated to provide the apparatus with a compact shape for ease of transportation and storage.

It can be seen that the drive unit 60 is located directly beneath a forward half of the seat member 32, and thus is located essentially immediately vertically beneath the torso of the operator. Thus, the drive unit 60 is mounted closely adjacent the centre of gravity of the watercraft when loaded and as such generates a propulsion force through a vertical axis of the centre of gravity, thus reducing a swivelling effect that could otherwise occur if the line of action of the propulsion force were displaced longitudinally or laterally from the vertical axis of the centre of gravity. This contributes to enhanced stability of the vessel when operated at cruising speed in relatively rough water and/or in strong winds. In addition, the drive unit 60 is located sufficiently forwardly to essentially eliminate accidental contact with the operator's legs or feet.
At cruising speed the operator generally leans backwardly, ie. towards the forward end of the watercraft, so as to

-14-partially lower the forward end, thus shifting the axis of rotation of the propeller 62 towards a generally horizontal position. When the operator is fishing, the operator would generally lean forwardly, ie. towards the rear of the watercraft. The downwardly and rearwardly inclination of the hull member 47 and the downwards bulging thereof provides additional volume adjacent the rear seat surface 40 for the seat member to expand into. This additional volume increases water displacement when the operator leans forwardly, thus reducing any tendency of the seat member to slope downwardly into the water, and thus reducing the chance of the operator slipping off the seat member and into the water. Care is taken to ensure that the bottom seat surface 44 is protected from possible damage from the strut 61 and the marine fitting 59.

While a specific embodiment of the invention has been described and illustrated, such embodiment should be considered illustrative of the invention only and not as limiting the invention as construed in accordance with the accompanying claims.

Claims (17)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A watercraft comprising:

(a) a generally U-shaped floatation member having (i) two laterally spaced apart side portions each having a forward end, a rearward end and a top surface; and (ii) a front end portion extending between said forward ends;

(b) a seat member disposed between said side portions and said front end portion, said seat member having a front seat surface adjacent the front end portion and a generally unobstructed, transversely extending rear seat surface disposed oppositely from said front seat surface;

(c) a rigid hull member located beneath said seat member and having a lower surface bulging downwardly below said floatation member; and (d) a drive unit for propelling said watercraft secured beneath said rigid hull member adjacent to a central longitudinal axis of said rigid hull member and generally adjacent a vertical axis passing through a centre of gravity of the loaded watercraft.

2. The watercraft as claimed in claim 1 wherein said floatation member is inflatable and deflatable.

3. The watercraft as claimed in claim 1 or 2 wherein said seat member has a bottom seat surface and two side seat surfaces, each of said side seat surfaces being complementary to and adjacent one of said side portions, said front seat surface is complementary to said front end portion, and said rear seat surface is disposed forwardly of said rearward ends of said floatation member.

4. The watercraft as claimed in claim 3 wherein said rigid hull member is located beneath said bottom seat surface and includes:

(a) a forward edge connected to said front end portion;
and (b) two side edges each connected to one of said side portions.

5. The watercraft as claimed in any one of claims 1 to 4 wherein said drive unit includes a propeller rotatable about a generally horizontal axis.

6. The watercraft as claimed in any one of claims 1 to 5 wherein said floatation member and said seat member are independently inflatable and deflatable.

7. The watercraft as claimed in any one of claims 1 to 6 wherein said side portions and said front end portion have generally similar circular cross-sections.

8. The watercraft as claimed in any one of claims 1 to 7 wherein said drive unit includes an electric motor and further comprising:

(a) a battery holder located on said floatation member;
(a) a manual control unit located within reach of an operator;

(b) electrical conduits extending from said battery holder to said control unit, and from said control unit to said drive unit to permit control of electrical power supplied to said drive unit.

9. The watercraft as claimed in any one of claims 1 to 8 further comprising a back support member extending upwardly above said front end portion.

10. The watercraft as claimed in claim 9 wherein said floatation member, said seat member and said back support member are independently inflatable and deflatable.

11. The watercraft as claimed in claim 9 or 10 further comprising:

(a) an air compressor unit having a discharge;

(b) air conduits extending from said discharge to each of said floatation member, seat member and back support member, each of said conduits having a respective control valve; and (b) electrical conduits extending from said compressor to said control unit to permit control of said compressor.

12. The watercraft as claimed in claim 9, 10 or 11 wherein said battery holder is located within said back support member and generally adjacent a central longitudinal axis of said watercraft.

13. The watercraft as claimed in any one of claims 1 to 12 further comprising two side storage compartments, each being connected to one of said top surfaces.

14. The watercraft as claimed in claim 13 further comprising two forwardly facing mirrors, each of said mirrors being connected to one of said side storage compartments.

15. The watercraft as claimed in any one of claims 1 to 13 further comprising:

(a) two forwardly facing mirrors located adjacent respective side portions of the floatation member.

16. The watercraft as claimed in claim 15, in which each mirror is moveable between a respective retracted position and an extended position.

17. The watercraft as claimed in claim 9 or 10 further comprising:

(a) an air compressor unit having a discharge;

(b) air conduits extending from said discharge to each of said floatation member, seat member and back support member, each of said conduits having a respective control valve; and (c) a manual control unit located within reach of said operator.